Preheat oven to 350° F. Spray 8 inch cake pan with pan spray and line bottom with parchment.
In a microwave safe bowl, melt the butter. Add in the chocolate chips and allow the warm butter to melt the chocolate.
In the bowl of stand mixer whip together the eggs and sugar on higher for about 5-7 minutes or until doubled in volume.
Add in the vanilla, salt, and cocoa powder and mix until well combined.
Slowly add in the melted chocolate and butter into the egg mixture and mix until well combined.
Pour batter into prepared 8-inch cake pan and bake for 40-45 minutes.
Allow to cool completely before slicing into three even layers.
Peanut Butter Cream:
Place white chocolate and peanut butter in a mixing bowl. Heat the cream until hot in a microwave safe bowl or in a small a saucepan over medium high heat. Pour the cream over the peanut butter and chocolate.
Bloom the gelatin sheets in ice water. Warm the softened gelatin until liquid and mix into the white chocolate and peanut butter mix.
In the bowl of stand mixer fitted with the paddle attachment beat the cream cheese for three minutes. Scrape the bowl and add the white chocolate peanut butter mix. Mix together until fully incorporated. Fold in the whipped cream. Keep cold.
Assembly
Line an 8-inch cake ring with acetate on a cookie sheet lined with parchment. Place one piece of cake down and pipe an even layer of peanut butter cream. Repeat. Place the cake in the refrigerator for at least one hour.
Place the cake on a cooling rack with a cookie sheet under the rack. Remove the cake ring and acetate. Pour the chocolate ganache on top, starting from the middle of cake. Allow chocolate to drape on to the sides sides of cake and ensure chocolate is covered around and evenly using an icing spatula. Decorate the top with chopped up peanut butter cups. Allow for chocolate to set up.